Abstract: A high-frequency surgical testing device for testing a neutral electrode during treatment, particularly during monopolar coagulation of biological tissue using a high-frequency current. The neutral electrode includes at least one first electrically conductive electrode segment having a first cable for connecting to a high-frequency generator, and a second electrically conductive electrode segment having a second cable for connecting to a high-frequency generator, the first and second electrode segments contacting the tissue. The test device includes an encoding element having a code for describing the neutral electrode and a measurement device for capturing the code describing the neutral electrode. The test device allows an identification of the neutral electrode to ensure safety.